title: Defect in recruiting effector memory CD8+ T-cells in malignant pleural effusions compared to normal pleural fluid.
abstract: BACKGROUND
  Malignant pleural effusions (MPE) are a common and fatal complication in cancers including lung or breast cancers, or malignant pleural mesothelioma (MPM). MPE animal models and immunotherapy trials in MPM patients previously suggested defects of the cellular immunity in MPE. However only few observational studies of the immune response were done in MPM patients, using questionable control groups (transudate…).
  
  
  METHODS
  We compared T cell populations evaluated by flow cytometry from blood and pleural effusion of untreated patients with MPM (n = 58), pleural metastasis of adenocarcinoma (n = 30) or with benign pleural lesions associated with asbestos exposure (n = 23). Blood and pleural fluid were also obtained from healthy subjects, providing normal values for T cell populations.
  
  
  RESULTS
  Blood CD4+ or CD8+ T cells percentages were similar in all groups of patients or healthy subjects. Whereas pleural fluid from healthy controls contained mainly CD8+ T cells, benign or malignant pleural effusions included mainly CD4+ T cells. Effector memory T cells were the main T cell subpopulation in pleural fluid from healthy subjects. In contrast, there was a striking and selective recruitment of central memory CD4+ T cells in MPE, but not of effector cells CD8+ T cells or NK cells in the pleural fluid as one would expect in order to obtain an efficient immune response.
  
  
  CONCLUSIONS
  Comparing for the first time MPE to pleural fluid from healthy subjects, we found a local defect in recruiting effector CD8+ T cells, which may be involved in the escape of tumor cells from immune response. Further studies are needed to characterize which subtypes of effector CD8+ T cells are involved, opening prospects for cell therapy in MPE and MPM.
authors.affiliation: INSERM Unit 1019, CIIL, Institut Pasteur de Lille, Lille, France. arnaud.scherpereel@chru-lille.fr
authors.forename: Arnaud
authors.initials: A
authors.lastname: Scherpereel
authors.forename: Bogdan Dragos
authors.initials: BD
authors.lastname: Grigoriu
authors.forename: Marc
authors.initials: M
authors.lastname: Noppen
authors.forename: Thomas
authors.initials: T
authors.lastname: Gey
authors.forename: Bachar
authors.initials: B
authors.lastname: Chahine
authors.forename: Simon
authors.initials: S
authors.lastname: Baldacci
authors.forename: Jacques
authors.initials: J
authors.lastname: Trauet
authors.forename: Marie-Christine
authors.initials: MC
authors.lastname: Copin
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Dessaint
authors.forename: Henri
authors.initials: H
authors.lastname: Porte
authors.forename: Myriam
authors.initials: M
authors.lastname: Labalette
mesh_terms: D000368:Aged; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology / Q000473:pathology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology* / Q000473:pathology; D005122:Exudates and Transudates / Q000276:immunology*; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D007156:Immunologic Memory / Q000276:immunology; D007694:Killer Cells, Natural / Q000276:immunology / Q000473:pathology; D008297:Male; D008654:Mesothelioma / Q000276:immunology* / Q000473:pathology; D008875:Middle Aged; D010996:Pleural Effusion / Q000276:immunology / Q000473:pathology; D016066:Pleural Effusion, Malignant / Q000276:immunology* / Q000473:pathology; D010997:Pleural Neoplasms / Q000276:immunology* / Q000473:pathology; D016176:T-Lymphocyte Subsets / Q000276:immunology / Q000473:pathology